Step tread



1949- R. H. HOCUTT 2,484,947

STEP TREAD Filed June 21, 1945' m Ha I l I I 19 16 19 20 a vg j Patented Oct. 18, 1949 2,484,947 STEP TREAD Rudolph Hovan Hocutt, Charlotte, N. C., assignor to Southern Friction Materials Company, a corporation of North Carolina Application June 21, 1945, Serial No. 600,758

1 Claim. 1

This invention relates to step coverings such as step treads and step nosings, and to other similar fittings such as moldings and the like.

A number of composition materials are available having adequate wear resistance and nonslip properties for use as step coverings. Such materials are well adapted for this purpose, particularly from the standpoint of cost. Difliculty has been encountered, however, in using these materials for step treads and the like because no practical method of equipping the step treads with a nose portion has heretofore been developed.

A nose portion for step treads is desirable not only to provide a complete protective covering for the step, but also to avoid the accident hazard inherent in a step covering having an exposed forward edge which is likely to work loose under the constant daily use to which steps are normally subjected.

The problem of equipping a step tread with a nose portion is complicated by the fact that steps are commonly installed in a variety of shapes and sizes. The usual procedure in view of this difficulty has been to provide a standard form of nose portion which requires working of the forward edge of the step to fit this form. This procedure is costly and inconvenient.

Moreover, in using composition materials as step coverings it is not possible to form an integral nose portion without employing a substantial forming radius, usually of the order of twice the thickness of the material being used. As a result, unless the forward edge of the step is worked to fit this forming radius, it is difficult to position the step covering so that the forming radius does not ride the forward edge of the step and prevent secure attachment of the covering to the step by raising the fiat portion of the covering from the top surface of the step near the forward edge.

These difiiculties are overcome according to the present invention by providing a universal type of nose portion for step coverings which will fit any of the various shapes and sizes of steps commonly in use. An important feature of my invention is the manner of forming the nose portion in the nature of a flange integral with the flat portion of the step covering and with the outer edge of the nose portion disposed substantially in underlying relation to the point on the flat portion at which the forming radius for the nose portion begins. This construction provides a nose portion arranged to engage the front edge of a step of any of the usual shapes or sizes in line contact so that no working of the forward edge of the step is necessary to fit the nose portion. Also, by disposing the nose portion in underlying relation to the fiat portion of the step covering the forming radius is positioned beyond the edge of the step and the fiat portion will lie properly on the top surface of the step.

Another important feature of my invention is that the above described construction provides a method of adapting relatively inexpensive composition materials for use as step treads and the like. In preparing step treads according to the present invention, for example, I may use a composition iabric material of the type disclosed in the copending applications of Snow, Serial No. 467,620, filed December 2, 1492, now U. S. Patent No. 2,424,861, and Serial No. 602,426, filed June 29, 1945, which comprises a fabric material impregnated with a thermosetting resin composition, cured to harden and set the impregnant, and then surface abraded to remove the hard and brittle impregnant curing crust and render the impregnated fabric material relatively flexible and smooth and gripping. Composition fabric materials prepared in this manner have excellent wear resistance and friction properties and are particularly well fitted for use as step covering material. These composition fabric materials are adapted for use according to my invention by a. sizing treatment with a penetrating thermosetting resin solution which takes a relatively rigid set so that the'nose portion can be set under the influence of heat substantially in place when formed.

Other composition materials may also be used if desired. Any impregnable material, for instance, which has been treated to fill up and body the material and invest it with adequate wear resistance and non-slip properties, and which may be formed and set under the influence of heat, may be used according to the present invention.

My invention is illustrated in the accompanying drawing in which:

Fig. 1 is a perspective view of a step tread formed according to my invention;

Fig. 2 is a diagrammatic sectional viewof a step fitted with a step tread of this type;

Fig. 3 is a corresponding sectional view illustrating the use of a nosing formed according to my invention;

Fig. 4 is a fragmentary sectional view illustrating a manner of forming the nose portion of step coverings; and,

Fig. is a diagrammatic representation of the manner in which the formed step coverings are arranged for final heat treatment.

As illustrated in Fig. 1, my invention comprises a step covering of the step tread type, which includes a fiat portion ll! adapted to be attached in covering relation on the top surface of a step, and a nose portion Il' integral with the fiat portion in and adapted to be disposed over the forward edge of the step. The nose portion II is formed in the nature of a flange along an edge of the flat portion l0, and as previously mentioned the outer edge of the nose portion II' is disposed substantially to underlie the pointon the fiat portion in at which-the forming ofthe:

nose portion H begins. That is, the flange formed by the above noted constructionof nose portion H is disposed with an underlying angularity with respect to the flat portion l0, and this underlying angularity is provided in a degree sufiicient to extend the outer edge of the flange underneath the fiat portion It beyond the point on the flat portion ill at which the forming of the nose portion begins, as described more in detail below.

The above described construction of the step covering is further illustrated in Fig. 2, which is a diagrammatic representation of the manner in which such a step covering is fitted to a step. In Fig. 2,.the step is shown at l2; the usual risers being indicated at l3. The step i2 is commonly formed at its forward edge with a rounded nose as at M, although in practice there is no standard shape of nose l4 and its form is apt to vary considerably from one installation to another. Also, the steps l2 are used in various widths and thicknesses. To provide a step covering which may be readily fitted to any of the various sizes and shapes of steps, it is accordingly necessary to arrange the step covering so that it may be fitted and adequately secured to the step without reference to the size or shape of the step. This result is accomplished according to the present inventionby arranging the nose portion 1 I so that it engages the nose I l of the step only in line contact (as at 55 in Fig. 2), and 'by further disposing the nose portion l l to underlie the fiat portion If) of the step covering so that the forming radius (or formed area adjacent the flat portion Hi) of the nose portion H is positioned clear of thestep nose l4 and thus has no tendency 'to disturb the engagement of the flat portion with that-op surface of the step I2.

As previously noted, a substantial forming radius is required for composition materials, which the present invention contemplates using as step coverings. A general rule is that the forming radius should be at least twice the thickness of the material being formed. Unless this large forming radius happens to fit the form of the step'nose ldexactly, it is apt to ride the nose I4 I so-that the flat portion it! of the step covering is raised from the forward portion of the top surface of the step it and cannot be properly secured to the step l2. If the fiat portion ll] of the step covering is fitted by forcing it into. contact with the top surface of the step !2 under these conditions, the nose portion ii is sprung to a protruding position so that it constitutes an accident hazard. This problem would not arise with a completely rigid material such as metal, or with a fully flexible material such as rubber, but these materials have disadvantages for use as tep covering, such as lack of proper friction properties in the case of metal and aging in the case of ruball) her, and they are relatively expensive so that there is accordingly considerable advantage in providing a means for using the less expensive and specially adapted composition materials.

In forming step coveringsaccording to the present invention, the difliculty occasioned by the large forming radius necessary with composition material is. avoided by constructing the nose portion I I so that the formingradius is spaced from the nose i l of the step i2 and does not affect the manner of fitting the step covering on the step. This: construction provides a universal type of nose portion ll so that the step coverings may be manufactured in standard sizes without regardto the particular step on which they are to be installed;

The' flatiportion- ID with which the nose portion I I is integrally formed, may also be made in standard tread sizes. Usually it is not necessary for the step covering torfit all the way to the rear risen ltlbecause the wear on the step 12 is encountered-in the forward area and adequate protective covering of. this portion is all that is needed. When-complete covering is desired, however, in: an :instance where a standard size does not fit exactly, the. next larger standard size may becut down,- or aznosingconstructed according to the present invention-with'a rear filling of some covering-material such'as linoleum might be used, as :illustrated inFig; 3.

In Fig. 3, the nosing comprises a fiat portion lt'which is of relatively short width but of sufficient surface area to allow secure attachment of the fiat portion lfi-on: the top surface of the step l2; and an integral nose portion ll constructed as described above; A nosing of this sort may be used to provide-a wear resistant and non-slip protective coveringfor. the forward portion and nose of a step in-combination with a. covering for the rear portion of the step of some standard floor covering material as indicated by the dotted lines in Fig. 3,

As. previously mentioned, step coverings may be constructed according to my invention from the composition fabric materials disclosed in the above identified copending applications. These materials compriseafabric material bodied with a thermosetting impregnant.composition (which is curedinsitu), and surfaceabraded to remove the-crust of hardened impregnant (which forms during. curing) and. condition, the composition fabric materials. withudesirable surface characteristics.

In using materials of thistype to form the step coverings of. my. invention, the, composition material, after being cut. to suitable step. covering dimensions is sizedin athermosetting resin solution which takesv arelatively hard set. Most any of the water soluble phenolic resins,.for example, may be used for thispurpose. The sizing treatment may be suitably carried out by dipping the composition fabricmaterial in. the sizing resin, running the sizedmaterial through squeeze rollers to removeexcess resin, andthen allowing the sized material to air dry for about 24 hours. After sizing the composition fabric material is ready for the step of forming the step covering nose portion.

The forming operation may be carried out as illustrated in Fig; 4. I have found that a form made'up of plywood sections or the like gives very satisfactory results. The form illustrated in Fig. l'comprises an upper ll and a lower l8 body section-spaced by interposed blocks 19. A

forming slot"20' is provided by-shaping'an edge of the upper section I I and related spacing block I9 togive the form of nose portion II desired, and then arranging a corresponding toe block 2| to complete the forming slot 20.

Forming of the nose portion l I is accomplished by inserting an edge of the sized composition fabric material cut to step covering dimensions in the forming slot 20, as indicated by the dotted lines in Fig. 4. The extending portion of the material being formed is then pressed over so that it lies flat on the upper section I! and is weighted in place. Usually, the forming operation will be facilitated by heating the composition fabric material for a short period just prior to forming. Heating at 250 F. for about minutes will give satisfactory results in most cases.

The forming means described above is particularly well adapted for use with composition materials because it will allow the material to form according to its natural characteristics. Composition materials, particularly materials of the type described in the above mentioned copending applications, are apt to vary to some degree in forming characteristics from piece to piece. In the case of composition fabric materials, for example, different characteristics are presented depending upon whether the form is effected lengthwise or across the weave of the base fabric. Slight differences in thickness or internal structure will also affect the manner in which the material forms. As a result, difiiculties are often experienced in forming composition materials by forcing them to the shape of a given form because the above mentioned variations will not as a practical matter allow exact uniformity of forming and if such uniformity is attempted, a high percentage of rejects results. The forming means of the present invention avoids this difficulty by allowing the composition material freedom during forming. That is, the composition material I0 is allowed to assume the form to which it is best adapted over the form block composed of the upper body section I! and interposed block I9, and is only held in place along an edge portion by the retaining or toe block 2| during forming. This arrangement allows a consistent underlying angularity for the nose portion I I to be obtained without encountering the difficulties which would result if the composition material were restricted at the forming radius during forming.

Weighting of the formed step coverings in place may be accomplished by-superimposing the forms as illustrated in Fig. 5. The forms are advantageously built up in tiers in this manner on a truck or dolly or the like, with a final weighting member 22 placed over the top form, so that they may be readily disposed in a curing oven to set the resin sizing. A cure at 200 F. for about 24 hours is usually required to harden the sizing sufficiently to set the formed nose portion I I in place. After treatment in this manner the step covering may be removed from the forms and a finish applied if desired.

The step coverings may be installed on a step with a cement of the waterproof type. The cement is applied to the surface of the step and also to the back of the step covering, and allowed to air dry for a few minutes until it becomes tacky. The step covering is then pressed down firmly on the step with the nose portion I I in contact with the nose of the step. As noted above, only line contact with the nose of the step occurs so that the installation may be carried out without regard to the form of the nose.

In forming a nose portion II for step coverings according to the present invention, I have found that an underlying angularity for the nose portion (as represented by the angle A in Fig. 4) of about 30 is more or less optimum. If this angle is lessened, the underlying disposition of the nose portion II tends to be inadequate, and a greater angle provides an excessive spacing of the forming radius from the nose of the step and thus causes the nose portion II of the step covering to protrude unduly.

The depth of the nose portion II will vary somewhat with the forming radius necessary for the composition material being used. In general the depth should be about four times the forming radius. This ratio, in combination with the underlying angularity of 30 mentioned above,

will in most cases dispose the nose portion II to underlie the fiat portion ID (or IE) of the step covering adequately in accordance with the present invention.

While the present invention has been illustrated and described with respect to its application in forming step coverings, it will be understood that it is also applicable in other similar instances, such as in forming moldings and the like, and that such similar applications are contemplated within the scope of the appended claim.

I claim:

A step covering formed of relatively rigid, inherently resilient thermosetting resin-impregnated fabric material comprising a fiat tread portion and a flanged nose portion adjacent one side edge, said nose portion having a flat flange portion projecting downwardly from and parallelly underlying the tread portion at substantially a 60 angle and a curved portion interconnecting the tread and flange portions, and

said curved portion having a radius of at least twice the thickness of the resin-impregnated fabric material from which the step covering is formed.

RUDOLPH HOVAN HOCUTT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Certificate of Correction Patent No. 2,484,947 October 18, 1949 RUDOLPH HOVAN HOCUTT It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 2, line 17, for the filing date, December 2, 1492 read December 2, 1942;

and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Oflice.

Signed and sealed this 11th day of April, A. D. 1950.

THOMAS F. MURPHY,

Assistant Oommz'ssz'oner of Patents. 

